Molecular Biology and Primate Phylogenetics (PDF file format—requires Adobe Acrobat Reader)
All life on Earth shares common ancestry. The more closely related any two organisms (the more recently in time any two creatures have diverged from a common ancestor), the more similar their DNA and the proteins coded for by that DNA. In this activity students will examine the amino acid sequence differences for a beta hemoglobin in several primate species, and from this infer ancestral relationships.
Questions for discussion or short essays:
Students will find these exercises akin to a pre-test, largely evaluating one's understanding either based on prior knowledge or on the brief presentation in the Prologue. They are therefore meant to provoke critical thinking. Much more information regarding each of these questions will be developed in greater detail in the principal epochs of this Web site.
1. What is the one major requirement for evolution, be it evolution of living matter or non-living matter? Explain why it is necessary.
2. What is the main difference between a prokaryote and a eukaryote? Which came first in Earth's history, and why?
3. What single event probably enabled life to move eventually out onto the land, and why was it able to do so?
4. Briefly describe the process of respiration. In what ways is it complementary to photosynthesis, and why it that important?
5. Order the following organisms according to time of prominence: birds, fermenting heterotrophs, dinosaurs, trilobites, mammals, insects, reptiles, worms, fish, amphibians, flowers, photosynthesizing prokaryotes.
6. Explain some of the factors likely leading to the biological "explosion" of life forms about 600 million years ago on Earth.
7. How might the first living organisms have become established on land, and what makes this such a difficult question for which to find evidence?
8. What three types of mammals developed during the Mesozoic Age?
9. What are the two main features of the fossil record that led to the idea of biological evolution? What is the basic idea of biological evolution, and how does it work?
10. Describe the concept of "speciation," also often termed "disruptive selection."
11. Explain the origin of the fossil fuels now used to power our modern civilization.
12. Discuss some of the early ecological crises on our planet, and how were they overcome?
True or False:
1. True or False: A heavy dose of energy was most likely needed to build the precursors to life, after which milder energy was needed to maintain them. _______ Explain your answer.
2. True or False: Although scientists suspect that photosynthesis occurred early in Earth's history, they have not found any evidence to support this claim. _______ Explain your answer.
3. True or False: An autotroph is an animal that does not need energy to survive. _______ Explain your answer.